Well now that the booking is showing in MMB, a seat they told me was not available is actually available. They told me it was assigned, not blocked.
So the agents don’t get to see seats that Golds have access to?
That might not be the case... that seat may have been assigned but that passenger has now cancelled his flight or re-assigned his seat. I do it all the time in the build up to T-72. As other seats fill or become vacant I move myself to what I consider my preferred seat. and I will do this everyday up to check in... and even after if I don't get my boarding card.
So you can't be sure it wasn't assigned when you/the agent looked